There have been proposals to crack down on speeding. There has even been a suggestion of zero tolerance of minor speed violations. In the United Kingdom, the Council for the Protection of Rural England is calling for a 40 mph speed limit on rural roads. Reductions in speed limits on roads are often largely ignored since drivers have become used to travelling on the road at the higher speed limit. Furthermore, local driving culture may be such that speed limits are generally ignored. In the UK for example, a great deal of motorway traffic travels at between 80 and 85 mph.
Police forces have already installed speed cameras in order that speeding motorists can be photographed and have points awarded to their licence or fines imposed without the need for intervention by a policeman. Conventional film based cameras have tended to have a margin of tolerance set into them in order that they only catch the worst offenders and thereby can be expected to have a reasonable lifetime before the film needs replacing. Film based cameras are slowly being replaced by digital cameras which do not have the same data storage problems. Furthermore, if the cameras have a telecommunications link then they are able to capture an image of every speeding vehicle that goes past them. If such cameras are set to a zero tolerance limit, it becomes entirely feasible for a driver committing only minor speeding offences to achieve sufficient speeding violations within a single journey to lose his license without him ever being aware of it.
Such a zero tolerance regime might result in many drivers spending a considerable amount of time looking at their speedometer and consequently less time looking at the road. Furthermore, excessively cautious drivers may drive at a larger margin below the actual speed limit causing unnecessary congestion, possibly frustration amongst other road users and even additional accidents.
For the rigid enforcement of speed limits, there are two numbers that the driver needs to know. These are what the local speed limit is, and the vehicle's speed is. Whilst the UK has, in general, a reasonably good sign posting system, it is always possible to miss a road sign when the driver's attention is directed elsewhere. This may be because of local traffic conditions requiring driver attention. Furthermore, it is not uncommon, especially on rural roads, for road signs to become obscured by overhanging trees in the summer or to appear as silhouettes when driving into bright sunlight. There has also been a tendency to increase the number of roadside signs, and this may increase further if roadside advertising or sign sponsorship is allowed, thus giving the driver far more peripheral and nonessential information to sift through before he can identify the local speed limit.
In the car, the speedometer is the most visible of instruments, but it is still provided in an instrument binnacle which requires the driver to avert his eyes from the road and to refocus on the distance to a few feet in front of him in order to read the vehicle's speed. Often an experienced motorist knows his approximate speed by the sound of the engine of his car. Where some minor speeding is tolerated, this is a sufficiently accurate technique for a motorist to regulate his road speed. However, if a zero tolerance regime is enforced, then the motorist can no longer rely on this audio clue, and will be forced to examine his speedometer far more frequently and consequently be looking at the road less frequently.